Review of THz near-field methods

Terahertz (THz) imaging offers many attractive advantages over existing modalities especially in its ability to obtain spectroscopic information. In particular, THz spectra are extremely sensitive to small changes of the molecular structure and different isomeric and intermolecular configurations. With a comparatively longer wavelength (0.3 mm at 1 THz), THz images suffer from the problem of low spatial resolution, as determined by Rayleigh's criterion and proves to be a major limitation. This paper reviews the existing THz near-field methods and recent developments for identifying potential areas of research